How to Use RPE and Reps in Reserve Without Any App

Published October 23, 2026 · Last reviewed October 23, 2026

What the scale measures

The version of RPE that suits lifting is built on repetitions in reserve (RIR): after the last rep of a set, how many more clean reps could you have done? In the scale tested by Zourdos and colleagues, a rating of 10 means zero reps left, 9 means one rep left, and so on down the scale, so RPE 7 is about three reps in reserve. In their study of 29 lifters, 15 with an average of about five years of training and 14 with an average of under a year, the rating moved in step with how fast the bar travelled: a strong inverse relationship between average bar speed and RPE in both groups (r = −0.88 in the experienced squatters and r = −0.77 in the novices). The authors call the scale a practical way to regulate daily training load (Zourdos et al., 2016).

Helms and colleagues describe the appeal in plain terms: the scale adjusts loads to match an athlete’s capabilities on a set-to-set basis (Helms et al., 2016).

How accurate is your own count?

Not perfectly, and it helps to know by how much. A scoping review and meta-analysis of 12 studies with 414 participants found that people tended to underpredict the number of reps they had left by about 0.95 of a rep on average, with large differences between studies. Predictions improved when they were made closer to the end of the set, with heavier loads and in later sets, and training status did not seem to change accuracy (Halperin et al., 2022). In practice that means treating a rating as a range of about one rep either side, not as a precise measurement. The abstracts of these studies do not report results separately for women, so a sex-specific difference is Not reported here.

A four-step method you can run with a pen

Action

Pick a target rating for the main working sets (for example RPE 7), choose a starting load, and write the weight and reps on a card.

Why it helps

A target gives each set a pass or fail test that does not depend on a percentage you may not have measured recently.

Verification

After the first working set you can name how many reps you had left, and the number sits within one of the target.

Action

Rate the last rep of each working set straight away and write the number beside the weight. Count only reps you would have done with your normal technique.

Why it helps

Predictions slightly improve in later sets, so the second and third sets are better evidence than the first.

Verification

Your card shows a rating for every working set, and the ratings sit within a point of one another.

Action

Adjust the next set: if a set felt easier than the target, add a small step; if it felt harder, drop the load or the reps.

Why it helps

The American College of Sports Medicine position stand recommends a 2–10% load increase when you can complete the current workload for one to two repetitions over the desired number (ACSM, 2009). That guidance is written for healthy adults, so lifters returning from injury should use the step their clinician sets.

Verification

Worked example: 60 lb is the current load, so 2% is 1.2 lb and 10% is 6 lb; the next rating is back near the target.

Action

Rate the whole session afterwards with one number from 0 to 10 answering “How was your workout?”, and write down how many minutes it took.

Why it helps

The session-RPE method has been checked in 36 validation studies across sports and physical activities, with men and women of different ages and expertise (Haddad et al., 2017).

Verification

You can compare this week’s rating and minutes with last week’s on the same card.

Where it goes wrong

Three mistakes account for most disagreements with the card. First, counting grinding reps: if the last rep looked nothing like the first, the set was closer to the limit than your rating says. Second, rating too early: decide after the set, not at the halfway point. Third, mixing exercises: a rating on a leg press does not carry over to a squat, so keep a separate line for each lift. These are practical notes rather than findings from the studies above.

Beginners can use the scale from the start. The meta-analysis found no clear effect of training status on accuracy, and the ACSM stand points novices to loads they can lift for about 8–12 repetitions. The first six months guide shows how that fits into a week, and the RPE load calculator converts a rating and a rep count into an approximate load.